Nortel Networks NN46110-602 - Manual (Page 91)

Chapter 4 Troubleshooting 91
Nortel VPN Router Troubleshooting
My downloaded DNS servers for my tunnel connection do not
work
Cause: The Microsoft Windows 95/98 and Windows NT operating systems
attempt to ping new DNS servers before adding them to the current list of servers.
Action: As a quick test, try to ping (with the tunnel connection active) the DNS
servers that the extranet device is downloading at tunnel startup. If you cannot
ping the servers, a basic connectivity problem using the tunnel connection exists.
To view the current list of DNS servers at any time use the MS-DOS command
ipconfig/all
on Windows NT or winipcfg on Windows 95 or Windows
98.
Why, after disconnecting a PPTP tunnel, do I get an immediate
error reconnecting?
Cause: After you disconnect a PPTP tunnel, then immediately try to reconnect,
the PPTP client indicates that the connection is busy or otherwise unavailable. On
Windows 95 this is caused by the PPTP control channel socket being improperly
shut down by the client.
Action: You can wait for the socket to time out, but it is often more expedient to
reboot. On Windows NT a similar problem is encountered, but caused by a TCP
checksum error generated by the Microsoft IP stack. The only current resolution
for the Windows NT error condition is to reboot.
Additional information
Below is a list of some of the Microsoft Knowledge Base topics you can browse
for information related to dial-up and tunnel configuration. To view these topics,
go to
www.support.microsoft.com/support . Use the Search Support Online feature
to search on the title you want:
• Troubleshooting Internet Service Provider Login Problems
• Service Pack 2 May Cause Loss of Connectivity in Remote Access
• Troubleshooting Modem Problems Under Windows NT 4.0
• Dial-Up Networking 1.2 Dun12.doc File (Windows 95 PPTP
Troubleshooting)